diff options
Diffstat (limited to 'lib/CodeGen/SelectionDAG/SelectionDAG.cpp')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index 8918c45562..765ff1b758 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -952,6 +952,27 @@ SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT, } } + // If this is a selectcc, check to see if we can simplify the result. + if (SetCCSDNode *SetCC = dyn_cast<SetCCSDNode>(N1)) { + if (ConstantFPSDNode *CFP = + dyn_cast<ConstantFPSDNode>(SetCC->getOperand(1))) + if (CFP->getValue() == 0.0) { // Allow either -0.0 or 0.0 + // select (setg[te] X, +/-0.0), X, fneg(X) -> fabs + if ((SetCC->getCondition() == ISD::SETGE || + SetCC->getCondition() == ISD::SETGT) && + N2 == SetCC->getOperand(0) && N3.getOpcode() == ISD::FNEG && + N3.getOperand(0) == N2) + return getNode(ISD::FABS, VT, N2); + + // select (setl[te] X, +/-0.0), fneg(X), X -> fabs + if ((SetCC->getCondition() == ISD::SETLT || + SetCC->getCondition() == ISD::SETLE) && + N3 == SetCC->getOperand(0) && N2.getOpcode() == ISD::FNEG && + N2.getOperand(0) == N3) + return getNode(ISD::FABS, VT, N3); + } + + } break; case ISD::BRCOND: if (N2C) |